[Typescript] Pick partially object type with indexed access types

type PartOfWindow = {
    [Key in 
      | "document"
      | "navigator"
      | "setTimeout"]: Window[Key]
}
/*
type PartOfWindow = {
    document: Document;
    navigator: Navigator;
    setTimeout: (handler: TimerHandler, timeout?: number | undefined, ...arguments: any[]) => number;
}
*/

We can refacotr the type to be more generalic

type PickWindowProperties<Keys extends keyof Window> = {
  [Key in Keys]: Window[Key]
}

type PartOfWindow = PickWindowProperties<"document" | "navigator" | "setTimeout">

Further:

type PickProperties<
  ValueType,
  Keys extends keyof ValueType
> = {
  [Key in Keys]: ValueType[Key]
}

type PartOfWindow = PickProperties<
  Window,
  "document" | "navigator" | "setTimeout"
 >

标签：PartOfWindow,Typescript,object,number,PickProperties,access,Window,Key,type
来源： https://www.cnblogs.com/Answer1215/p/16599829.html